johngwheeler

I know this is a very general question to which this answer is probably "it depends", but from your own experience, what multiplier would you apply to your "typical" gravel rides to get an approximate equivalent in either time/distance/effort/average speed to a paved road ride?

For example, you might find your average speeds on your usual gravel routes to be two-thirds of you average road speed, or estimate the total time or effort for a gravel ride to be twice an equivalent distance road ride.

This will naturally depend greatly on the type of gravel road, but I'm trying to get some ball-park metrics.

I may take part in a gravel ride that has two options: 50km & 130km. If it were a pure road ride, I would go for the 130km because I'm confident of finishing this, even with a fair amount of climbing. But a 130km gravel ride might be too much for me. The 50km sounds a bit short - but it could be "just right" if it involves the same effort as a 100-120km ride on paved surfaces.

BTW, I would be riding this on a Giant CX bike with either 35mm Schwalbe Marathons or 40mm Clement MSOs.

Thanks!

dgodave

Great question.

For my riding, I'd say 0.66 gravel = 1.00 road. On average. That includes some quite rough dirt roads. I might have to revise this as I think about it tho.

130k is quite a jump from 50k. But I'd feel almost cheated only getting to ride 50k.

79pmooney

Uphill, some to lots, I just rode Oregon's Trask Trail to the coast on a fix gear. (With options to change cogs to gears down to 41".) We hit some 18% grades with loose gravel. On a paved surface, hard but quite doable. On that? Twice, just getting over the short 18% stuff took everything I had. Everything. The third time, I stalled and fell over. Walked the rest of the steep stuff. I don't have a number for you, but it can be a LOT harder. One huge change is that where you stand on pavement and get a welcome beak from sitting is often exactly where you cannot stand on gravel because the rear tire slips.

Ben

johngwheeler

My thoughts exactly! I don't want to pay almost the same entry fee, travel to the same point (at least 2 hours from home, possibly requiring an overnight stay because of the early start), and just do a steenkin' 50 klicks..... But a 130km gravel ride makes me pause for thought.... Depends on the gravel, I guess!

Spoonrobot 

Here's my breakdown based on average speed for a given course, the courses I've ridden are generally 34-70 miles and between 50-130 feet per mile. I will say I've definitely ridden a 31mile (50km) gravel/dirt course that was as hard as a 62 mile (100km) road ride with the same elevation in feet/mile.

• Small or medium gravel with compact dirt underneath, dry or wet, 50 ft/mile or less - Difficulty is 100%-110% of road riding, average speed is 90%-100% of road speed.
• Small or medium gravel with compact dirt underneath, dry or wet, 50-75 ft/mile - Difficulty is 110%-120% of road riding, average speed is 80%-90% of road speed.
• Small or medium gravel with compact dirt underneath, dry or wet, 75-100 ft/mile - Difficulty is 120%-130% of road riding, average speed is 70%-80% of road speed.
• Large gravel or soft dirt or 100+ feet a mile, wet or dry - Difficulty is 150-175% of road riding, average speed is 56-66% of road speed.

The list makes it seem easier than reality. I would rank the list as:

• Easy/Normal
• Hard
• Very Hard
• Extreme

ksryder

Completely subjective, anecdotal answer based entirely on my perception and not backed up by any empirical evidence:

Gravel = 1.5 road miles
MTB = 2 road miles.

mstateglfr 

a 30mi gravel ride is like a 50mi road ride for me. Thats based on how I feel afterwards.

u235

I've never really noticed a difference. In the extreme, I've done a 4 day tour on gravel of 75+ miles each day. My knees eventually became the weak point followed by my upper arms. After day 4 I had given up mentally and physically, luckily my trip was done as no way I would have done a 5th day. To be fair, that may have happened on an equivalent road trip too, not sure. I ride 30+ miles on the road several times a week but no long trips.

espressogrinder

I typically noticed about a 2 mph difference. 15-16 mph on a typical gravel road here in Michigan turns into 17-18 when I hit pavement with same perceived effort.

ksryder

A little OT but the conversion for wear-and-tear on parts is not directly proportional to perceived effort. To wit:

I replace components on my gravel bike 3-4x as often as on my road bike. Some things (like rims) I have *never* replaced on a road bike, but I ended up wearing through the brake tracks on a set of TB-14s in about 2 years.

I'm not sure if this is more or less than I would replace parts on a MTB because I rarely ride MTB enough to wear things out.

RJM

I'd say it totally depends on the route. Most of the gravel routes around me are pretty hilly and the hills are generally steeper than the road and the gravel gets deep and rutty, so I would say 2 road miles equals 1 gravel mile.

On the mtb I can ride a 10 mile ride and feel like I rode a 40 mile road ride.

dgodave

Unless youre well trained/prepared, day 5 or 6 of a tour will be a real low point.... but after that youll feel increasingly better.

My experience anyway.

Marcus_Ti

Dependent on tire size and pressure, and the surface condition/terrain.

TimothyH

This was quantified fairly well by an experienced gravel rider/racer in post number 5.

johngwheeler

Great answers, guys; Thank you!

It does sound like I need to study the surface that I will be riding on to get a more accurate picture, but I could go with a "rule of thumb" of 1.5-2 times the estimated effort/time for the same distance - if it turns out to be easier, then so much the better.

dgodave

'
It would have to be pretty awful conditions for it to be 2x, imo. I mean, parts of it may be that bad. But would an event really make you ride 130k of mushy gravel?

ksryder

Land Run is pretty close most years, but to be fair, that is really more of a Tough Mudder-style event, with occasional biking, than than a bike race.

Overall I'd agree with you, 2x is the high end, but we're also talking about something that you really can't apply a scientific exact conversion formula to.

Marcus_Ti

The 2017 Land Run 100 Experience - Stillwater, Oklahoma - Gravel Cyclist: The Gravel Cycling Experience

LR was an absolute mess by all reports. I read the above in my own comfortable warm den and still shivered. Reports were not only muddy and wet but cold. People were going hypothermic. More than a few people crashed because they were barely able to control bikes due to cold.

Of maybe 1300 people registered, 1000 started....and only 100 or so finished.

dgodave

I think a long difficult ride is a great thing.

But I cant see the point at all of setting out deliberately on a giant mud-slog... let alone paying for it.

Marcus_Ti

No kidding. There comes a point where it just ain't fun to do anymore.

I had signed up for Heatstroke 100 on Sunday here (road and gravel routes)....active T-storms in the area all morning and lots of wet roads NVM mudpits for the non-pave route. I and a few local mates just decided after a long work week that we'd be riding it for pride rather than fun and stayed home.

ksryder

Word. I ride because it's fun. I've done two significant muddy rides: DK 2015 (finished) and Land Run 2016, where I DNF at mile 20 because my non-replaceable RD hanger completely sheared off. Drove 4 hours to Stillwater, biked for an hour, and drove 4 hours back home.

Not fun.

Not saying LR can't be fun, but I'm not willing to spend another 8 hours in the car to find out.

FBinNY 

Toss a coin and do either. If 130km road would have been a stretch, or pushed the time limit, play it safe and have an enjoyable shorter ride this time out, and get a better sense of your gravel pace and range.

xraydog

I agree with expressogrinder. I ride relatively flat packed gravel rail trail and notice I ride about one gear heavier (about 2mph faster) on flat roads. Hill climbing is another animal, basically because the gravel road turns to loose rocks, so much harder than road.

wheelsmcgee

I went on a gravel ride over the weekend and averaged a little over 16mph...maybe similar distance/effort on pavement I'd be at 18 or so, so a multiplier of *maybe* 1.2. However, this was mostly flat and smooth/packed gravel.

On rides with lots of rolling hills, I think the multiplier is higher...compared to pavement, some gravel roads aren't as good at letting you take advantage of all that potential energy you accumulate on the uphill when you are on the way downhill...one year at DK, I felt like I rode the brakes on every downhill because of the instability of the road or because there was some sort of washout at the bottom. Of course, when you add a fresh layer of chunky rock so that riding is like plowing a field, that doesn't help either.

bobwysiwyg

Must be me and my cowardice but how fast you can go on gravel depends a good deal on the kind of gravel, is it damp or dry and how quickly you might have to stop or avoid the unexpected.